1. Field
The invention relates to an organic electroluminescence display device and a manufacturing method thereof, and more specifically, to an organic electroluminescence display device encapsulated by a frit and a manufacturing method thereof.
2. Discussion of the Related Technology
In general, organic electroluminescence display devices comprise a substrate on which a pixel region and a non-pixel region are provided, and a vessel or another substrate arranged to be opposite to the substrate and attached to the substrate by a sealant such as epoxy for its encapsulation.
On the pixel region of the substrate are formed multiple light-emitting elements connected in a matrix form between a scan line and a data line, the light-emitting elements comprising an anode electrode and cathode electrode, and an organic thin film layer formed between the anode electrode and cathode electrode, the organic thin film layer comprising an hole transport layer, an organic light-emitting layer and an electron transport layer.
The light-emitting elements configured as described above are susceptible to oxygen exposure because of they contain organic materials. They are also easily oxidized by moisture in the air since the cathode electrode is made of metal materials and can suffer deterioration to electrical and light-emitting properties. To mitigate the above problems, a powder-type moisture absorbent or a film-type moisture absorbent on a vessel manufactured in the form of a metal material can or cup, or a substrate made of glass, plastic, etc. is provided to take up moisture, oxygen and hydrogen penetrated from the exterior.
However, such a method of coating the powder-type moisture absorbent requires complicated processes and raises cost for materials and the processes. In addition, the method results in an increase of the thickness of the display device and further it is difficult to be applied to an screen light-emitting type. In addition, the method of attaching the film-type moisture absorbent has limited ability to eliminate all the moisture and also has low durability and reliability, thus limiting application in the production in large quantities. The above discussion is simply to describe the general field of organic light emitting displays and is not a discussion of the prior art.
Methods have been employed which encapsulates light-emitting elements by forming side walls with frits to overcome the afore-mentioned problems.
International patent application No. PCT/KR2002/000994 (May 24, 2002) discloses an encapsuation container formed with side walls using a glass frit and a manufacturing method thereof.
U.S. patent application Ser. No. 10/414,794 (Apr. 16, 2003) discloses a glass package encapsulated by attaching a first and a second glass plates through a frit and a manufacturing method thereof.
Korean patent laying-open gazette No. 2001-0084380 (Sep. 6, 2001) discloses a frit frame encapsulation method using a laser.
Korean patent laying-open gazette No. 2002-0051153 (Jun. 28, 2002) discloses a packaging method of encapsulating an upper substrate and a lower substrate with a frit layer using a laser.